/*
 * Copyright (c) 2004,2013, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.bundle.serial;

import java.io.IOException;
import java.util.Dictionary;
import java.util.Hashtable;

import javax.comm.CommPortIdentifier;
import javax.comm.PortInUseException;
import javax.comm.SerialPort;

import org.osgi.framework.BundleContext;
import org.osgi.framework.ServiceRegistration;
import org.osgi.service.device.Device;

import org.knopflerfish.service.serial.SerialPortDevice;

class SPD
  implements SerialPortDevice
{
  private static final int SERIAL_WAIT = 1000;
  private static final String[] clazzes = new String[] {
                                                        Device.class.getName(),
                                                        SerialPortDevice.class
                                                            .getName() };

  private ServiceRegistration<?> sreg;
  private boolean dying;
  private CommPortIdentifier cpi;
  private SerialPort sp;

  void start(BundleContext bc, String port, String product, String revision)
      throws Exception
  {
    cpi = CommPortIdentifier.getPortIdentifier(port);
    if (cpi == null) {
      throw new IOException();
    }

    final Dictionary<String, Object> props = new Hashtable<String, Object>();
    props.put("DEVICE_CATEGORY", new String[] { "Serial" });
    props.put("DEVICE_DESCRIPTION", "Serial device");
    props.put("org.knopflerfish.service.serial.port", port);
    props.put("org.knopflerfish.service.serial.product", product);
    if (revision != null) {
      props.put("org.knopflerfish.service.serial.revision", revision);
    }

    if (dying) {
      return;
    }
    sreg = bc.registerService(clazzes, this, props);
    synchronized (this) {
      if (!dying) {
        return;
      }
    }
    close();
  }

  void close()
  {
    synchronized (this) {
      if (sreg == null) {
        dying = true;
        return;
      }
    }
    sreg.unregister();
    synchronized (this) {
      releaseSerialPort();
      cpi = null;
    }
  }

  public synchronized SerialPort allocateSerialPort()
  {
    if (cpi != null && sp == null) {
      try {
        sp = (SerialPort) cpi.open("serial", SERIAL_WAIT);
      } catch (final PortInUseException e) {
      }
      return sp;
    } else {
      return null;
    }
  }

  public synchronized void releaseSerialPort()
  {
    if (sp != null) {
      sp.close();
      sp = null;
    }
  }

  public void noDriverFound()
  {
  }
}
